Abstract: In recent years, hydrogen energy is the hotspot and frontier of research at home and abroad. The generation of hydrogen from water-electrolization by solar energy plays a significant role in achieving carbon emission peak and carbon neutrality. Aiming at the low flexibility of existing photovoltaic electrolysis direct coupling system and its inability to apply on a large scale, an optimal strategy of dynamic adjustment under the dual array is proposed in this paper. Based on the complex model of the photovoltaic-electrolytic dual array, the operating characteristic of electrolyzers is deeply analyzed and the photovoltaic maximum power curve is piecewise linearized with the least square (LS) technique. The operating principle of the working point in this direct coupling system is explained from the matching perspective of the I-U characteristic curve under the photovoltaic array and the electrolytic array. Finally, the simulation results verify the effectiveness of the strategy, which shows that with high efficiency to utilize the photovoltaic energy, this strategy increases the flexibility of system and the rate of hydrogen production. Moreover, it provides reference for the research on the photovoltaic electrolytic water hydrogen production technology and the development of the hydrogen energy industry.